One of the highlights of my recent trip to Peru was seeing Andean condors in the wild. I knew that they’re the largest raptor in the world, and South America’s largest flying bird—males can weigh a whopping 33 pounds and have a 10-foot-long wingspan—but I didn’t fully appreciate how enormous they are until they soared a mere 20 feet over my head.

To find the magnificent creatures, I went to Colca Canyon. It was an experience of extremes—at 10,725 feet, the canyon is among the deepest in the world, and the condors that live there fly to heights of nearly 3.5 miles. If you go early in the morning, however, you can see them fairly close up at Cruz del Condor, a rocky lookout.

Photo: Alisa Opar

When showing a patient friend numerous photos when I got home, he joked, “Are those birds going to eat those people?”

“Of course not,” I said. “They only eat dead things…I think.”

Photo: Alisa Opar

In need of more info, I turned to Michael Mace, curator for birds at the San Diego Zoo's Wild Animal Park and the coordinator for the Andean Condor Species Survival Plan.

“As big as they are, they just eat carrion,” says Mace. “They’re scavengers.”

They might occasionally go after a downed animal, or a newborn, Mace explains, but the misconception that they hunt cattle, sheep, and other livestock has led ranchers to kill them, causing their population to decline. The birds’ body parts are also used in some traditional medicines; legend has it that the stomach cures breast cancer, for instance, and that roasted eyes will improve eyesight. Today their conservation status is “near threatened.”

Photo: Alisa Opar

Mace has been helping to release Andean condors back into the wild in Colombia, Peru, and Venezuela, with the hopes of bolstering populations. Late this year or in early 2011, Mace plans to send two young condors to Colombia, bringing the total released into the wild to 82 since 1990 (the chicks are raised in American and Colombian zoos). One of the two birds was hatched at the San Diego Zoo.

Mace and others are also looking to expand the release program to other areas in South America to create a contiguous population throughout the Andes, rather than isolated populations.

Andean condor conservation can benefit more than just one species, Mace explains.

“When we go into a region to do a release, we also have a public education aspect,” he says. “Getting people to understand the importance of this charismatic species, of a flagship species, and protect their habitat also protects many other animals that are not as charismatic.”

Photo: Alisa Opar

The two condors Mace hopes to release later this year will each be about a year old when they’re set free. The birds have much in common with California condors, whose numbers plummeted to fewer than two dozen in the early 80s and have climbed to 350 in birds, about 180 of which are flying free in California, Arizona, and Baja, Mexico. As with California condors, Colombian biologists have tracked and monitored released birds, and found that some have begun to breed.

“Both Andean condors and California condors are now raising offspring in the wild,” says Mace. “It’s just incredible to see this go full cycle.”

Photo: M.W. Furshong

Fun fact from the folks at the San Diego Zoo: Unlike most vultures, it’s easy to tell the sex of Andean condors:

Andean condors are the only New World vultures to show sexual dimorphism. Males are usually larger and have a distinctive comb on top of their head, as well as a large neck wattle and yellow eyes. The females lack the comb and have red eyes. The males keep the comb all their life, which makes it easy to tell the sex of an Andean condor chick as soon as it hatches. As adults, both sexes have black plumage with white secondary feathers and white neck ruffles. Juveniles have brown plumage and skin and don’t develop adult coloring until they are about six years old.